Device and method for repairing pipe

ABSTRACT

A liner tube is provided for repairing either a single pipe line or a main pipe line having a lateral pipe line connected thereto. The liner tube assembly includes a liner tube impregnated with a liquid material capable of curing and hardening. The liner tube includes a gasket or band positioned about the juncture of the pipe lines. The gasket or bands form a tight seal between the liner tube and the pipe line.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a Continuation of Application of U.S. Ser. No.13/161,581 filed Jun. 16, 2011, which is a Continuation Application ofU.S. Ser. No. 11/845,134 filed Aug. 27, 2007, now U.S. Pat. No.7,975,726 issued Jul. 12, 2011, all of which are incorporated byreference in their entirety.

BACKGROUND OF THE INVENTION

The present invention relates to a device and method for repairing pipe,such as underground sewer pipe and the like.

Prior methods for repairing damaged pipe lines include moving a linertube impregnated with a liquid material capable of curing and hardeningto the position within the pipe where the damaged portion is located.The liner tube is urged in an outward radial direction into contact withthe pipe line being repaired and the liquid material impregnating theliner tube is permitted to cure and harden. The liner tube forms aninterior liner in the pipe for the pipe line being repaired.

On some occasions lateral pipe lines are connected to main pipe lines.Often damage occurs at the junction between the lateral pipe line andthe main pipe line. T-shaped or Y-shaped liner tubes have been utilizedto fit within the junction between the lateral pipe line and the mainpipe line. Liner tubes form a T-shaped or Y-shaped liner after hardeningto the interior of the junction between the lateral pipe line and themain pipe line.

Ground water outside the lateral pipe line and the main pipe lineinfiltrates through the damaged portion of the pipe line and migratesbetween the liner tube and the pipe line to a point where it can enterthe pipe line. In order to prevent this infiltration of ground water,attempts have been made to adhere the liner tube to the interior surfaceof the pipe line being repaired, whether it is a single straight pipeline or a T-shaped or Y-shaped pipe line.

However, considerable difficulty has been encountered in attempting toobtain an adhesive bond between the liner tube and the interior of thepipe being repaired. The interior of the pipe being repaired is oftengreasy or oily even after high pressure water jetting is performed.Attempts have been made to wash the interior of the pipe line with somesuccess, but washing the interior of the pipe line is often only partialand not reliable. Furthermore, in some types of pipes, such aspolyethylene pipes, an adhesive bond cannot be maintained between theresin impregnated liner tube and the polyethylene pipe even if the pipeis free from grease and oils.

Even in those instances where the interior of the pipe line is suitablefor accepting a liner, shrinkage of the liner can occur, which creates agap that allows ground water to flow around the liner and eventuallyinfiltrate the pipe line. For example, thermoset resins are used incured-in-place pipe applications to form the liner to the interior ofthe pipe line. These thermoset resins tend to shrink during the curingprocess, thus creating a gap between the liner and the pipe. Even theslightest shrinkage in the liner can be problematic.

U.S. Pat. No. 6,994,118 addresses some of these problems in the art. Thepresent invention constitute improvements and additions to the earlierdisclosure.

A primary object of the present invention is the provision of animproved device and method for repairing pipe by using hydrophilic sealsor other impermeable compressible materials.

A further object of the present invention is the provision of a deviceand method for preventing ground water from infiltrating a pipe linenear the juncture between a main pipe line and a lateral pipe line.

A further object of the present invention is the provision of a deviceand method for repairing a section of a pipe and preventing entry ofground water from a damaged portion of the pipe being repaired.

A further object of the present invention is the provision of a deviceand method for repairing the juncture between a main pipe line and alateral pipe line which uses a hydrophilic band or similar article ofimpermeable compressible material positioned between the main pipe lineand the liner around the opening that connects the main pipe line to thelateral pipe line.

A further object of the present invention is the provision of a deviceand method for repairing the juncture between a main pipe line and alateral pipe line which uses a hydrophilic gasket or gasket of similarimpermeable compressible material that seals against entry of groundwater at the juncture between the pipe lines.

A further object of the present invention is the provision of a deviceand method for repairing pipe using hydrophilic seals and the like whichis economical to manufacture, durable in use, and reliable in operation.

BRIEF SUMMARY OF THE INVENTION

According to one feature of the present invention, an apparatus isprovided for repairing the juncture between a main pipe line and alateral pipe line. The apparatus includes a main liner member and alateral liner tube made of resin absorbent material. A hydrophilicgasket or gasket of similar impermeable compressible material surroundsa portion of both the main liner member and the lateral liner tube andis positioned between the host pipes and the liner assembly inoperation. The hydrophilic gasket is capable of swelling in response tobeing exposed to a liquid, such as water, and forms a seal between theliner assembly and the host pipes at the juncture between the hostpipes. The apparatus can be used in applications where the lateral lineris inverted into the lateral pipe line or in so-called “pull-in-place”applications. In a pull-in-place application, both the main liner andlateral liner are moved through the main pipe line to a position wherethe lateral liner ultimately extends inside the lateral pipe line andthe main liner is positioned in the main pipe line near the accessopening to the lateral pipe line.

According to another feature of the present invention, a hydrophilicband or band made of a similar impermeable compressible material ispositioned on the main liner portion of a main/lateral liner. The bandsurrounds the opening between the main and lateral liners and isdisposed between the main pipe line and the liner around the peripheryof the opening between the main and lateral pipes to effectively sealagainst entry of ground water at the pipe junction. Again, thisapparatus is suitable for use in both inversion-style applications andpull-in-place applications.

According to yet another feature of the present invention, an apparatusand method for inverting a liner in a cured-in-place application isprovided. The liner includes two hydrophilic bands connected to theinterior lining surface of the liner that are spaced apart from oneanother a sufficient distance so as to create a seal between the hostpipe and the liner on opposite sides of the damaged portion of the pipe.When the liner is inverted, the hydrophilic bands are positioned on theoutside of the liner between the host pipe and the liner. Exposing thehydrophilic bands to water or other liquid causes them to swell, therebycreating the desired seal.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a repair assembly for repairing alateral pipe line and a main pipe line.

FIG. 2 is a sectional view of a main pipe line and a lateral pipe lineshowing one embodiment of the present invention.

FIG. 3 is a view similar to FIG. 2, but showing the liner in itsinflated position.

FIG. 4 is a perspective view of an alternative embodiment of a repairassembly for repairing a lateral pipe line and a main pipe line.

FIG. 5 is a sectional view of a main pipe line and a lateral pipe lineshowing the device in FIG. 4.

FIG. 6 is a view similar to FIG. 5, but showing the liner in itsinflated position.

FIG. 7 is a sectional view of a pipe line, showing another embodiment ofthe present invention.

FIG. 8 is a sectional view similar to FIG. 7, showing the liner in apartially inverted position.

FIG. 9 is a sectional view similar to FIG. 8, showing the liner in afully inverted position.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to FIGS. 1-3, a repair assembly is generally designated by thenumeral 10. Repair assembly 10 includes a launcher device 12 havingmounted thereto a T-shaped or Y-shaped liner assembly 14. Repairassembly 10 also houses a T-shaped or Y-shaped bladder assembly 16. Inthe particular configuration shown in FIGS. 1-3, the liner assembly 14and bladder assembly 16 are T-shaped, but they can also be Y-shaped toaccommodate a lateral pipe line that intersects with a main pipe line atan oblique angle.

Launcher device 12 includes side walls 18, an end cap 20 and an end wall22, all of which form a launcher device cavity 48. End cap 20 includes aline inlet 24 through which a line 26 extends. Line 26 is attached to aclosed bladder tube end 28. Also extending through end cap 20 is an airinlet 30 which is connected to an air hose 32. T-shaped or Y-shapedbladder tube assembly 16 includes a main bladder tube 34 and a lateralbladder tube 36. Similarly, the T-shaped or Y-shaped liner assembly 14includes a main liner tube 38 and a lateral liner tube 40. The bladderassembly 16 is fitted on the interior of the liner assembly 14.

As can be seen in FIG. 1, the main liner tube 38 is comprised of what isinitially a flat sheet of material which is wrapped around the outsideof the main bladder tube 34 and the launcher device 12. The main linertube 38 includes overlapping edges 42, 44. The launcher device 12includes a launcher device opening 46, and the lateral liner tube 40 iscontained within the launcher device cavity 48 as shown in FIG. 2.Similarly, the lateral bladder tube 36 is contained within the cavity 14and surrounds the lateral liner tube 40. Both the main liner tube 38 andthe lateral liner tube 40 are comprised of a felt layer, which is thelining surface that contacts the interior surface of the host pipe, anda polymer coating is on the opposite surface.

FIGS. 2 and 3 show the repair assembly 10 within a main pipe line 50which is connected to a lateral pipe line 52. The damaged portion 54 isshown needing repair. Ground water from outside the lateral pipe line 52and the main pipe line 50 will seep through the damaged portion 54 andenter the interior of the main pipe line 50 and the lateral pipe line52.

In order to prevent this seepage of ground water, a gasket 56 ispositioned about a portion of the liner assembly 14. The gasket 56includes a tubular portion 60 that extends at least partially within thelateral liner tube 40 and a flange portion 58 that extends outwardlyabout the periphery of one end of the tubular portion 60. The flangeportion 58 of the gasket 56 is preferably attached to the main linertube 38 around the juncture between the main liner tube 38 and thelateral liner tube 40 so as to maintain the gasket 56 in proper positionas the repair assembly 10 is positioned for operation. The gasket 56 ispreferably made of a hydrophilic material capable of swelling inresponse to being exposed to water or other liquid. However, othermaterials for the gasket 56 found suitable include neoprene rubber,other similar gasket materials such as urethane or silicone rubber, andlike impermeable compressible materials.

FIG. 2 shows the repair assembly 10 moved within the main pipe line 50adjacent the lateral pipe line 52. The launcher device opening 46 isregistered with a junction between a lateral pipe line 52 and the mainpipe line 50. This alignment is done with a TV camera (not shown). Thelateral bladder tube 36 and the lateral liner tube 40 are containedwithin the launcher device cavity 48. It should be noted that thelateral liner tube 40 and tubular portion 60 of the gasket 56 extendwithin the lateral bladder tube 56 in FIG. 2; whereas, the main linertube 38 and the flange portion 60 of the gasket 56 remain outside themain bladder tube 34 on the exterior of the launcher device 12.

Air pressure is introduced in the cavity 48 through air hose 32, urgingthe liner tube assembly 14 into contact with the interior walls of themain pipe line 50 and the lateral pipe line 52. Continued air pressurecauses the lateral bladder tube 36 and the lateral liner tube 40 toinvert outwardly through the launcher device opening into the lateralpipe line 52 from the position shown in FIG. 2 to the position shown inFIG. 3. While air is the preferred pressurized material, other gasses orfluids may be used. It should be noted that this inversion processcauses the lateral liner tube 40 to be placed on the outside of thebladder tube 36 once the inversion is complete, as shown in FIG. 3. Inthis position, the gasket 56 is positioned between the main liner tubeassembly 14 and the interior walls of the main pipe line 50 and betweenthe lateral liner tube assembly 16 and the interior walls of the lateralpipe line 52. Pressure within cavity 48 is maintained until the liquidhardenable material, preferably a resin activated with a catalyst, curesand hardens. This results in the liner assembly 14 assuming a rigidconfiguration, forming a lining to the lateral pipe line 52 and the mainpipe line 50.

The gasket 56 is preferably made of a material which is hydrophilic andwhich is capable of expanding in response to encountering ground wateror other liquid. A manufacturer of such hydrophilic material is DeNeefConstruction Chemical Co., 18314 Mathes Road, Waller, Tex. 77484, underthe trademark SWELLSEAL™.

The ground water, as designated by the arrows 90 in FIG. 3, can seeptowards the hydrophilic gasket 56. However, upon encountering thehydrophilic gasket, the water causes the gasket to expand in both aradial inward direction and a radial outward direction. This causes thegasket 56 to form a water tight seal between the T-shaped or Y-shapedliner assembly 14 and the interior walls of the main pipe line 50 andthe lateral pipe line 52.

While the preferred embodiment of the invention is intended for use withan inversion-type application wherein the lateral bladder tube 36 andthe lateral liner tube 40 invert outwardly into the lateral pipe line52, those skilled in the art will appreciate that the gasket 56 can alsobe used in pull-in-place applications. In a pull-in-place application,the gasket can be threaded down the lateral liner tube 40 to thejuncture between the main liner tube 38 and the lateral liner tube 40.In such a pull-in-place application, it is less important that thegasket 56 be attached to the liner assembly 14, as the gasket 56 willtend to stay in proper position as the lateral bladder tube 36 andlateral liner tube 40 are moved through the main pipe line 50 andultimately into the lateral pipe line 52 while at the same time the mainbladder tube 34 and main liner tube 38 are moved along the main pipeline 50 to a position adjacent the opening to the lateral pipe line 52.

Although the precise dimensions of the gasket are not necessarilycritical to the present invention, a tubular portion having a length ofapproximately 6 inches and a flange portion 60 having a diameter ofapproximately 12 inches has been found suitable for most sewer pipeapplications.

FIGS. 4, 5 and 6 illustrate an alternative embodiment of the presentinvention wherein the gasket 56 is replaced with a ring-shaped band 62of hydrophilic material or like impermeable compressible material. Theband 56 is positioned on the main liner tube 38 and extends around thejuncture between the main liner tube 38 and the lateral liner tube 40.The band 62 is again preferably made of a hydrophilic material andswells in response to being exposed to water or other liquid. Inspecific, the band 62 expands outwardly and inwardly in a radialdirection to effectively seal the area between the liner assembly andthe juncture between the main pipe line 50 and lateral pipe line 52.

In applications where the lateral liner tube 40 is inverted into thelateral pipe line 52, it is preferred that the band 62 is attached tothe main liner tube 38 to secure the band in place. The band can beattached by means of stitching, stapling, or by use of an adhesive orsimilar attachment means. The band 62 may be made from a hydrophilicmaterial such as the one provided by DeNeef Construction Chemical Co.(described previously). A hydrophilic paste can also be used to form thering or band 62 on the main liner tube 38. One such hydrophilic paste isdistributed by OCM, Inc. in Vernon Hills, Ill. under the trademark ADEKAULTRA SEAL, part number P-201. This product is a single componenthydrophilic paste used in water stop repairs. The band 62 may also bemade from a paste that is no hydrophilic yet forms an impermeablecompressible gasket when cured. One such impermeable compressible pasteis distributed by Manus Products, Inc. in Waconia, Minn.

FIGS. 7, 8 and 9 illustrate another version of the present invention.Although U.S. Pat. No. 6,994,118 discloses the use of hydrophilic sealspositioned between the host pipe and the liner tube on opposite sides ofthe damaged portion of a pipe line, simply moving the liner tube andbladder into position along the pipe line has well-known disadvantagesnot experienced by inversion techniques. The present invention alsoincludes an embodiment wherein hydrophilic seals or bands can bepositioned on opposite sides of a damaged portion of a pipe line throughan inversion-style lining technique. FIG. 7 illustrates a singular pipe70 having a damaged portion 72. A launcher device 92 houses a liner tube74 and a bladder tube 84 and is positioned in the pipe 70. About theinterior lining surface of the liner tube 74 is a first hydrophilic bandor seal 76 and a second hydrophilic band or seal 78 spaced apart so asto be located on opposite sides of the damaged portion 72 of the pipe 70when the bladder tube 84 and liner tube 74 are inverted. The first andsecond hydrophilic bands or seals 76, 78 are attached to the interiorlining surface of the liner tube 74 by stitching, stapling, by use of anadhesive or other suitable attachment means.

FIG. 8 shows the liner tube 74 and the bladder tube 84 is a partiallyinverted position.

FIG. 9 shows the liner tube 74 and the bladder tube 84 fully invertedwherein the liner tube 74 is positioned at the damaged portion 72 andthe first and second hydrophilic bands or seals 76, 78 are located onopposite sides of the damaged portion 72 of the pipe 70. In theseinstances where the lining begins a significant distance away from thelauncher device, the bladder tube 84 acts as a positioning tube with theliner tube 74 positioned accordingly inside the bladder tube 84, so thatthe liner tube 74 does not invert until it reaches the damaged portion72 of the pipe 70.

The liner tube 74 comprises a layer of felt-like material which isimpregnated with a liquid material capable of curing and hardening andmay have a polymer outside layer or coating. The bladder tube 84 isinside the liner tube 74 after inverting and includes a closed end 86and a line 88 extending outwardly there from. Air or fluid is introducedinto the interior of bladder tube 84 to urge the bladder tube 84radially outwardly so as to urge the liner tube 74 into contact with thetube 70 being repaired.

The first and second hydrophilic bands or seals 76, 78, when encounteredby ground water seeping through the damaged portion 72 will expand andform a water tight seal on opposite sides of the damaged portion 72.This prevents water from entering the interior of the pipe line 70.

Those skilled in the art having the benefit of this disclosure willappreciate that in some applications a single band or seal can be usedto prevent ground water from entering the interior of the pipe line. Forexample, in lining a lateral pipe towards a main pipe, positioning ahydrophilic band at the downstream end of the liner prevents groundwater from running down between the liner and pipe and emptying backinto the pipe line.

The invention has been shown and described above with reference to thepreferred embodiments, and it is understood that many modifications,substitutions, and additions may be made which are within the intendedspirit and scope of the invention. The invention is only to be limitedby the claims appended hereto.

What is claimed is:
 1. A liner assembly for repairing an existing sewerpipe comprising: a body portion comprising a resin impregnatablematerial for extending into a lateral portion of a sewer pipe; a flangeassembly supported by the body portion, the flange assembly including acollar portion extending into a main portion of a sewer pipe; and a sealattached to the collar portion of the flange assembly for sealingagainst an inner surface of the main portion of the sewer pipe, whereinthe seal comprises a hydrophilic gasket.
 2. The assembly as recited inclaim 1, wherein the collar portion comprising a resin impregnatablematerial attached to the body portion.
 3. A method of lining a sewerpipe comprising: positioning a liner assembly within a sewer pipe,wherein the liner assembly includes a body portion of resin absorbablematerial and a flange assembly attached to the body portion, the flangeassembly including a collar portion for extending around an opening of alateral portion of the sewer pipe at a junction between the lateralsewer pipe and a main sewer pipe and a hydrophilic gasket secured to thecollar portion; aligning the collar portion with the opening to thelateral portion of the sewer pipe; applying a fluid pressure within thebody portion to extend the lateral portion within the lateral portion ofthe sewer pipe, and holding the body portion against an inner surface ofthe lateral portion until resin absorbed within the body portion cures;and applying a fluid pressure against the collar portion to force thehydrophilic gasket against an inner surface of the main sewer pipesurrounding the opening to the lateral portion until the body portionand the collar portion are cured.
 4. The method as recited in claim 3,wherein the body portion and the collar portion comprises a resinabsorbable material.
 5. The method as recited in claim 3, includingsupporting the flange assembly about the opening to the lateral portionof the sewer portion with the body portion such that no adhesive bond isformed against the inner surface of the sewer pipe.
 6. The method asrecited in claim 5, wherein the seal comprises a material expandableresponsive to exposure to water.
 7. The method as recited in claim 3,including the step of inflating a bladder having a body part and alateral part to hold the body portion of the lining assembly against ininterior surface of the main sewer pipe.
 8. The method as recited inclaim 7, including the step of inflating the lateral part afterinflating the body portion to install the lateral portion of the liningassembly into the lateral sewer pipe.
 9. The method as recited in claim7, including the step of pressing the hydrophilic gasket against aninner surface of the main sewer pipe surrounding the lateral openingwith pressure from the main part of the bladder.
 10. The method asrecited in claim 3, wherein the hydrophilic gasket attached to thecollar portion provides an improved seal at the junction between thelateral sewer pipe and the main sewer pipe.
 11. The method as recited inclaim 7, including the step of deflating the bladder after the linerassembly is cured and maintaining sealing contact between the innersurface of the main sewer pipe after removal of pressure against thecollar portion.
 12. A liner assembly for lining a junction between amain sewer pipe and a lateral sewer pipe comprising: a lateral portioncomprising a flexible resin impregnable material forming a tube; a mainportion including a resin impregnable material attached to the lateralportion, the main portion extending a distance outward from the lateralportion for surrounding an opening in the main sewer pipe for thelateral sewer pipe; and a hydrophilic seal supported on one of thelateral and main portions for sealing a junction between the main sewerpipe and the lateral sewer pipe, wherein the hydrophilic seal comprisesa gasket supported on the main portion.
 13. The liner assembly asrecited in claim 12, wherein the main portion includes a central openingabout which the lateral portion is attached.
 14. The liner assembly asrecited in claim 13, wherein the hydrophilic seal is annular andsurrounds the opening and the lateral portion.
 15. A liner assembly forlining a junction between a main sewer pipe and a lateral sewer pipecomprising: a lateral portion comprising a flexible resin impregnablematerial forming a tube: a main portion including a resin impregnablematerial attached to the lateral portion, the main portion extending adistance outward from the lateral portion for surrounding an opening inthe main sewer pipe for the lateral sewer pipe; and a hydrophilic sealsupported on one of the lateral and main portions for sealing a junctionbetween the main sewer pipe and the lateral sewer pipe, wherein the mainportion comprises a first surface for contacting an inner surface of themain sewer pipe and the hydrophilic seal is supported on the firstsurface.
 16. The liner assembly as recited in claim 12, wherein the mainportion comprises an annular portion that extends about the lateralportion.
 17. The liner assembly as recited in claim 13, wherein thefirst surface includes a first width between an outer edge of the mainportion and an interface with the lateral portion with the width beinggreater than a width of the hydrophilic seal.
 18. The liner assembly asrecited in claim 17, wherein the first width is greater than at leasttwice the width of the hydrophilic gasket.
 19. The liner assembly asrecited in claim 12, wherein an interface between the main portion andlateral portion are flexible for conforming to an irregular shape of thejunction between the main sewer pipe and the lateral sewer pipe.
 20. Theliner assembly as recited in claim 19, wherein the hydrophilic seal isflexible to conform to an irregular shape of the junction between themain sewer pipe and the lateral sewer pipe.
 21. The liner assembly asrecited in claim 20, wherein the hydrophilic seal is flexible to conformto an irregular inner surface of the main sewer pipe.
 22. The linerassembly as recited in claim 12, wherein the hydrophilic seal issupported entirely on the main portion.
 23. The liner assembly asrecited in claim 15, wherein the hydrophilic seal is supported entirelyon the main portion.